Prior art simulation systems tend to fall into three categories. The first category is paper and actor-based simulations, which use paper-based scripts and skilled facilitators who decide how participant behavior affects the simulation. These simulations are often run in a room with a staff of assistants who deliver paper messages. Like the first category, the second category also involves the use of scripts, but attempts to increase fidelity by involving often very large numbers of participants in-situ. These participants may be actors playing the part of injured civilians, military personnel, vehicles, and other entities all operating in the real world according to the simulation's script. These simulations tend to require many months of planning, are difficult to stage, hard to repeat, and often tremendously costly.
The third category involves computer-based simulation of real-world entities. In these systems, such as BCD Modelling's TUTOR, BreakAway, Ltd.'s Incident Commander, and Advanced Systems Technology's EPiCS, simulations are created by creating models of the real world in a computer. The systems include pre-built computational models. These existing simulations tend to be difficult to control and tend to focus exclusively on first-responders, such as police dispatchers. Such simulations generally fail to gauge the effectiveness of senior-level strategies, whose effects are often both profound and very subtle.